Deformation characteristics of Zhejiang soft soil deep foundation pits and their predictive analysis

Due to many influential factors of the deformation of deep foundation pit, a unified summary research of 37 deep foundation pits in Zhejiang province(Hangzhou mostly) is proposed according to the different conditions of excavation depth. This paper analyzes the characteristics of inclinometer curve of deep foundation pits and the surrounding settlement curve under the background of Zhejiang soft soil; the relationship between maximum lateral displacement and excavation depth of foundation pits is obtained. Experimental results show that: maximum lateral displacement points of Zhejiang soft soil deep foundation pits are between 4m above the excavation surface and 7 m below the excavation surface; maximum settlement in parabolic settlement curves generally occurs at a distance of 0.5 times the excavation depth; maximum settlement and maximum lateral displacement increases linearly with the depth of excavation; the relationship between the maximum lateral displacement and maximum subsidence is mainly influenced by the soil quality. Based on the further statistics and the characteristics of lateral displacement curve, this paper proposes a method for forecasting lateral displacement curve of foundation pit which is in well agreement with the measured value.